I found an article today in Homebrew Digest #5471 written by Rick Theiner, the chemist who developed One Step and Straight-A products.
Here is a quote from the article regarding One Step: "One Step was originally intended to be a final rinse type of product. I cannot legally call it a sanitizer because the cost involved in doingthat (registering with the EPA, etc.) is cost prohibitive for me.

HOWEVER, one of my associates has successfully convinced themanufacturer of the active ingredient (i.e. the guys that have thebig bucks) to register it as an algeacide/fungicide for use in watertreatment and agricultural use. We have not been able to get themto do the same for hard surface sanitizing, but this might give youan idea regarding the capacity of sanitizing for this type of product. If anyone is interested, they can check out the EPA review documenthere--

Anyway, the point is that I wanted to make One Step a single stepsanitizer to compete with iodophors (Star San was not available then). It is also a reasonably good cleaner, but the tough stuff is Straight-A. And a big caveat is that you cannot clean and sanitize the samesurface at the same time. So you should always pre-clean a surfaceprior to sanitizing (regardless of the product)."

I think this reasonably puts to rest the worries about whether you can use One Step as a sanitizer. I used it with no problems for a long
time until someone told me that it couldn't be used as a sanitizer. So for the new brewers, pre-clean with your favorite cleaner such as PBW or Straight-A,
and then sanitize with One Step or Star-San.

Last edited by Mob_Barley on Fri Dec 19, 2008 9:22 am, edited 2 times in total.

Actually, the article contradicts itself. He plainly states..."And a big caveat is that you cannot clean and sanitize the same surface at the same time. So you should always pre-clean a surface prior to sanitizing (regardless of the product)."

Given that, One Step is NOT an effective sanitizer unless you actually use it twice, once to clean the vessel, dump it out, and then re-use it as a "sanitizer". If I'm going to do that anyway, I'll stick to a product that is actually "legally" called a sanitizer.

I was actually thinking that the "one step" meant you can sanitize but you don't have to rinse. Not a clean AND sanitize in one step product. I think it may have been one of the first "no rinse" products since star san wasn't around when it was first put on the market, hence the name, one step.

Dont fear the foam. I find that Starsan is by far the cheapest way to go. I make mine up with RO/DI water, it stays crystal clear unless it gets dirty. Since I'm using it as a sanitizer, it only comes into contact with clean items. I reuse it until it turns cloudy (which means either it has been corrupted by dirt or somehow got diluted enough by regular tap water).

I purchased a gallon of starsan when I started brewing, and I am just about to purchase another gallon. I'd have gone through way more bags of onestep in that time if I had used it as a sanitizer. Being that onestep works like an oxygen cleaner, means it cant be reused over and over. Starsan is good as long as the ph is below 3.5.